CN1870465B - Generating method, communication system and communication method of circulation training sequence - Google Patents

Abstract

A generation method of a circular training sequence containing two training symbols includes: randomly growing a first information clock with the length of N, copying the last L data before the first information block as the circulation prefix of the first training symbol, forming the first information block to the information block of the second training symbol in the same length with the first information block in terms of the circulation mode, namely, the second information block, in which, the circulation mode is to shift the last d data of the first block to the start position and copy the last L data of the second block before the second block as the training prefix of the second training symbol, so that the two symbols form a circulation training sequence.

Description

Generation method, communication system and the communication means of circulation training sequence

Technical field

The present invention relates to a kind of circulation training sequence group that is used for multi-user system realization/down-going synchronous, i.e. circulation (Round-Robin) training sequence group.Also relate to a kind of communication system and the communication means that use this circulation training sequence group.

Background technology

The algorithm of existing a lot of classics is used for carrying out down-going synchronous [1]-[7].Yet in multi-user system, uplink synchronous normally compares difficult, especially when the multi-user adopts full multiplexing transmission mode.This is because different user has different distances with the base station in the uplink, thereby has when different inclined to one side.In addition, different user uses different oscillators, makes the centre frequency of these oscillators to have nothing in common with each other; Simultaneously, because the translational speed difference of different user, thereby different Doppler frequency shifts produced.More than two kinds of reasons will cause different user to have different carrier wave frequency deviations with respect to same base station.

A lot of classic algorithm utilize the duplicate message in the training sequence to carry out time synchronized and Nonlinear Transformation in Frequency Offset Estimation.In the base station,, utilize this phase angular displacement can estimate this user's carrier wave frequency deviation because the influence of carrier wave frequency deviation will produce a phase angular displacement between the duplicate message in the training sequence.In the multi-user system of full multiplexing transmission mode, the training sequence that sends when different user is during in the base station mutual superposition, if these training sequences have structure identical or that part is identical, then corresponding phase angular displacement will comprise a plurality of users' carrier wave frequency deviation information, that is to say that each user's carrier wave frequency deviation information will be lost separately.Phase mutual interference between this training sequence may cause the failure of certain user's synchronized algorithm.

List of references [1]-[7]

[1]J.-J.van?de?Beek?and?M.Sandell，“ML?estimation?of?time?and?frequencyoffset?in?OFDM?systems，”IEEE?Trans.Signal?Processing.，vol.45，pp.1800-1805，July?1997；

[2]H.Nogami?and?T.Nagashima，“A?frequency?and?timing?period?acquisitiontechnique?for?OFDM?system，”Personal，Indoor?and?Mobile?Radio?Commun.(PIMRC)，pp.1010-1015，September?27-29，1995；

[3]M.Morelli?and?V.Mengali，″An?improved?frequency?offset?estimator?forOFDM?applications，″IEEE?Commun.Lett.，vol.3，pp.75-77，March?1999；

[4]T.Keller?and?L.Piazzo，“Orthogonal?Frequency?Division?MultiplexSynchronization?Techniques?for?Frequency-Selective?Fading?Channels，”IEEEJournal?on?Selected?Areas?in?Communications，vol.19，No.6，pp.999-1008，June2001；

[5]T.M.Schmidl?and?D.C.Cox，“Robust?Frequency?and?TimingSynchronization?for?OFDM，”IEEE?Trans.Comm.，vol.45，pp.1613-1621，December?1997；

[6]P.H.Moose，“A?technique?for?orthogonal?frequency?division?multiplexingfrequency?offset?correction，”IEEE?Trans.Comm.，vol.42，pp.2908-2914，October1994；

[7]Z.Zhang?and?M.Zhao，″Frequency?offset?estimation?with?fast?acquisitionin?OFDM?system，″IEEE?Commun.Lett.，vol.8，pp.171-173，Mar.2004。

Because the interference distortion between the training sequence that different user sends might cause the inefficacy of certain user's uplink synchronous, thereby in the full multiplexing transmission mode uplink synchronous of multi-user system, provide one group of new reliable and stable training sequence to be very important with the interference distortion that reduces between the different user.

Summary of the invention

The problem that causes the inefficacy of certain user's uplink synchronous for the interference distortion between the training sequence that solves the different user transmission, and in order to realize high-precision down-going synchronous.

First purpose of the present invention provides a kind of generation method of new circulation training sequence group.

Second purpose of the present invention provides a kind of communication system of using this circulation training sequence.

The 3rd purpose of the present invention provides the communication means according to this circulation training sequence.

According to a first aspect of the invention, the generation method of circulation training sequence group is provided, this circulation training sequence comprises the generation method of the circulation training sequence of first training symbol and second training symbol successively, this first training symbol comprises first Cyclic Prefix and first information piece successively, and second training symbol comprises second Cyclic Prefix and second block of information successively.Wherein, this generation method comprises step:

First step, generating length at random is the first information piece of N, N is a natural number;

Second step from the first information piece that generates, copies a last L data before the first information piece to, and as the Cyclic Prefix of first training symbol, wherein L is the natural number less than block of information length;

Third step, with the first information piece of first training symbol mode according to circulation, form second block of information identical with first information block length, wherein, before endless form is meant last d data in the first information piece is displaced to before (N-d) individual data, rearrange N data that obtain and form second block of information, the corresponding relation between this first and second block of information is the architectural feature of this circulation training sequence, and wherein d is 0 or less than any natural number of block of information length; And

The 4th step copies last L data of second block of information that generates before second block of information to, as the Cyclic Prefix of second training symbol, thereby forms complete circulation training sequence.

According to a second aspect of the invention, provide a kind of communication system of using above-mentioned circulation training sequence, wherein, this communication system comprises:

User side, the architectural feature based on the specific circulation training sequence of base station assigns generates the circulation training sequence corresponding with architectural feature, adds certain data symbol, forms complete frame and sends as sending signal; And

The base station utilizes this specific circulation training sequence, and the signal that receives is carried out time synchronized and Nonlinear Transformation in Frequency Offset Estimation, and by behind the demodulation sign indicating number, recovers the transmission signal of user side.

According to a third aspect of the invention we, provide a kind of communication means that uses circulation training sequence, it is characterized in that this communication means comprises step:

First step, the user sends the request of access by Common Control Channel to the base station;

Second step: the circulation training sequence resource table is searched in the base station after the access request that receives this user, and there are a plurality of circulation training sequences with different structure feature in still unappropriated training sequence in the retrieval base station in this circulation training sequence resource table;

Third step, the base station is from the still unappropriated circulation training sequence that retrieves, select one of them, and send an answer message to this user, the distribution condition of notice circulation training sequence, refresh the distribution operating position of circulation training sequence in the circulation training sequence resource table of base station simultaneously, wherein, include the specific architectural feature of this circulation training sequence in this return information;

The 4th step, the user generates complete frame and sends it to the base station according to the specific architectural feature of the circulation training sequence that is comprised in the return information that receives, and wherein, this complete frame comprises data symbol and specific to user's circulation training sequence; And

The 5th step, receiving system carries out time synchronized and Nonlinear Transformation in Frequency Offset Estimation to the signal that this user sends in the base station, and behind the demodulation sign indicating number, recovers user's transmission signal.

The invention has the beneficial effects as follows: when this circulation training sequence group was used for down-going synchronous, net synchronization capability was better than traditional training sequence, can realize high-precision down-going synchronous; When carrying out uplink synchronous, the synchronization failure that this circulation training sequence group can avoid the training sequence mutual superposition because of different user to cause; When (N-1) individual user inserts same base station simultaneously at most, this circulation training sequence group can reduce the stack between multi-user's training sequence and interference distortion between the different user that causes, thereby can guarantee that each user can realize reliable and stable uplink synchronous.

Description of drawings

Fig. 1 has shown a kind of new circulation circulation training sequence S provided by the invention;

Fig. 2 has shown the schematic diagram that inserts a base station according to of the present invention one new user;

When Fig. 3 has shown new user's access base station, according to the structure chart of communication system 1 of the present invention;

Fig. 4 has shown according to the present invention, the structure chart of the transmitter 2 of user m;

Fig. 5 has shown the structural representation according to the receiver 3 of the base station of circulation training sequence S provided by the invention;

Fig. 6 has shown the structural representation according to timing tolerance of the present invention and Nonlinear Transformation in Frequency Offset Estimation device 51;

Fig. 7 is to use the algorithm of circulation training sequence group provided by the invention and Moose algorithm application to compare schematic diagram in the performance of uplink carrier frequency offset estimating;

Fig. 8 is the schematic diagram that circulation training sequence S specific timing tolerance of the present invention changes along with the variation of SINR and synchronous error

Fig. 9 has shown that circulation training sequence group of the present invention and Moose algorithm application are in the performance comparison figure of downlink carrier frequency offset estimating.

Embodiment

The present invention mainly is devoted to solve on the multi-user system/the down-going synchronous process in the design problem of training sequence.The invention provides one group of circulation training sequence efficiently, can realize down-going synchronous accurately, in realizing multi-user's uplink synchronous process, can eliminate the synchronization failure that causes owing to the stack between a plurality of users' the training sequence simultaneously, reduce the interference distortion between the different user that causes owing to the stack between a plurality of users' the training sequence, thereby can guarantee that each user can realize reliable and stable uplink synchronous.

＜circulation training sequence 〉

Fig. 1 has shown a kind of new circulation training sequence S provided by the invention.

This new circulation training sequence S comprises 2 training symbol t1 and t2 that length is identical, and wherein first training symbol t1 and second training symbol t2 comprise block of information and cyclic prefix CP.Here, the block of information length of training symbol t1 and t2 is N, and the length of cyclic prefix CP is L, then training symbol t1 and t2 length separately all is N+L, wherein, N is natural number arbitrarily for example 64,128,1024 etc. in the existing standard, and L is any natural number less than N.

Circulation training sequence S of the present invention (comprising first training symbol t1 and second training symbol t2) can generate by following steps:

Step a). generate the block of information of first training symbol t1, i.e. the first information piece of training sequence, the data of first information piece wherein can be to generate at random;

Step b). from the block of information that step a) generates, copy last L data of this first information piece the cyclic prefix CP 1 of the front of first information piece to as training symbol t1;

Step c). with the block of information of training symbol t1 according to the cycle arrangement mode, form the block of information of second training symbol t2, finger is displaced to back d data in the first information piece before preceding (N-d) individual data, rearrange N data that obtain and form second block of information, the corresponding relation between this first and second block of information is the architectural feature of this circulation training sequence;

Step d). last L data of second block of information of the training symbol t2 that generates in the step c) are copied to before the block of information among the training symbol t2, as the cyclic prefix CP 2 of training symbol t2.

As can be seen from Figure 1, above-mentioned steps a)-block of information of second training symbol t2 that step d) generated and the block of information of training symbol t1 generates through different change in location by identical data, wherein, the data arrangement in the block of information among training symbol t1 and the t2 is different in proper order.

Specify the cycle arrangement mode below.

Suppose to comprise N the data { x (0) that is arranged in order in the block of information of training symbol t1, x (1), ..., x (N-1) }, then in above-mentioned step b), with last L the data { x (N-L) in the block of information of training symbol t1, x (N-L+1), ..., x (N-1) } copy among the training symbol t1 before the block of information, as the cyclic prefix CP 1 of training symbol t1.

Then, in step c), according to the block of information of training symbol t1, the block of information of training symbol t2 is designed to { x (N-d), x (N-d+1) ... x (N-1), x (0), x (1), ..., x (N-d-1) }, 0≤d＜(N-1) wherein just is displaced to last d data of the block of information of training symbol t1 before first data of its block of information, and other data in the block of information move after in turn, thereby have formed the block of information of training symbol t2.Here, the description of back for convenience is referred to as d circulation training sequence S with the circulation training sequence S that moves the mode of a last d data and form, and it has d architectural feature.

Then, in step d), with last L data of the block of information of training symbol t2 x (N-d-L), x (N-d-L+1) ..., x (N-d-1) } copy to before the block of information among the training symbol t2, as the cyclic prefix CP 2 of training symbol t2.Training symbol t1 of Sheng Chenging and t2 have constituted circulation training sequence S of the present invention jointly thus, and have data dependence between the data of the block of information among training symbol t1 and the t2.

For different d, the circulation training sequence S of generation is also different.Simultaneously, for the training symbol t1 that has generated, because d can get (N-1) individual different value in theory, training symbol t2 can have (N-1) to plant possible arrangement, plants different circulation training sequence S thereby generate (N-1).

Because the d value between all circulation training sequences is different, make base station assigns reduce for the interference between each user's the circulation training sequence, and, because the d value is different, first training symbol of each circulation training sequence and the data dependence between second training symbol also have nothing in common with each other, and therefore, can prevent the interference between each circulation training sequence of base station end better, thereby, can carry out better each user on/wait down synchronously processing.

＜new user's access procedure 〉

All users' circulation training sequence S is distributed unitedly by the base station of its access among the present invention.The distribution of each user's circulation training sequence is to finish in the moment of the initial access base station of this user.All preserve a table in each base station, i.e. circulation training sequence resource (TSR, Training Sequence Resource) table.Store the base station in this TSR table and can distribute to access user's the architectural feature (d value) of ID, circulation training sequence S of all circulation training sequence S and the distribution operating position of each circulation training sequence S (for example whether this circulation training sequence S has distributed and distributed to which user or the like).Table 1 has shown according to circulation training sequence resource table of the present invention.

Table 1

Circulation training sequence ID	Architectural feature (the d=of circulation training sequence?)	Whether circulation training sequence distributes	Distribute to which user
				S0
	0	Be	The user 1
				S1	1	Be	The user 2
…	…	…	…
				S(N-1)	N-1	Not

The schematic diagram of the communication that Fig. 2 has shown when a new user inserts a base station, carry out between itself and the base station.For a new user m to be accessed, before its access base station, do not have base station assigns and give its specific circulation training sequence S.For the base station that this user requires to insert, the circulation training sequence that is comprised in its signal that utilizes this user to send carry out this user on/down-going synchronous.

When describing this new user m access base station in detail hereinafter with reference to Fig. 2, and the communication between the base station.When new user m request inserted, the step of the communication of being carried out between itself and the base station was:

A) user m sends the request of access by Common Control Channel (C-CH) to the base station;

B) the TSR table is searched in the base station after the access request that receives this user, retrieves the circulation training sequence of the still unallocated user of giving in base station in this table, has a plurality of circulation training sequence S with different structure feature (being different d values) in this TSR table;

C) base station is from still unallocated user's the circulation training sequence S of giving that retrieves, select one of them, and send an answer message to this user m, notify the distribution condition of circulation training sequence and the architectural feature of the operable circulation training sequence S of this user, wherein include the specific architectural feature of this circulation training sequence S in this return information.Simultaneously, the distribution operating position of circulation training sequence S in the TSR table is refreshed in the base station;

D) user m is according to the specific architectural feature of the circulation training sequence S that is comprised in the return information that receives, generation comprises specific to the circulation training sequence S of user m and the complete frame of user data, and this complete frame is sent to the base station as sending signal by wireless channel;

E) time synchronized and Nonlinear Transformation in Frequency Offset Estimation are carried out to the complete frame that receives from this user m in the base station, and by the demodulation sign indicating number, recover the transmission signal of this user m.

In the above communication means according to circulation training sequence S of the present invention, owing to provide the S of the circulation instruction row sequence with different structure feature to different user, thereby in the uplink synchronous of full multiplexing multiple-user system process, even if different training sequence mutual superposition, accurate uplink synchronous also can be carried out to each user in the base station, reduces multi-user's training sequence mutual superposition and the interference distortion that causes.

Instruction row sequence S total (N-1) plant because the present invention circulates, so same base station can be inserted (N-1) individual user simultaneously, it can satisfy complete multiplexing multi-user system capacity.And circulation training sequence S of the present invention is because its design feature also can realize high-precision down-going synchronous.

Usually, the number of users that can support of base station is far longer than the number of users of actual access.Even when number of users occurring and surpassing the number of users that can support to insert in the base station, the present invention also can carry out the scheduling that the user inserts in the following manner.

Promptly, in above-mentioned steps b, there is not the circulation training sequence (all circulation training sequences in base station all distribute) that to distribute to new access user m in the TSR table, at this moment, a circulation training sequence S who has distributed to certain (some) user can be found out in the base station in the TSR table, it is distributed to the user of this new access, and these users that use same loop training sequence S are carried out temporal scheduling, guarantee that the identical circulation training sequence S that these users send can not superpose in the base station.

＜communication system 〉

When Fig. 3 has shown new user's access base station, according to the structure chart of communication system 1 of the present invention.Below in conjunction with Fig. 3 this communication system 1 is described.

As shown in Figure 3, this communication system 1 has a plurality of users and a base station.Wherein, each user has the transmitter 2 that is used to send its transmission information.This base station has receiver 3, and receiver 3 has a plurality of receiving systems 4.Each receiving system 4 carries out communication with the transmitter 2 of the respective user of access base station respectively.User's transmitter 2 and the receiver 3 in the base station communicate according to the described method of Fig. 2.

When a plurality of user's access base station, the mutually different circulation training sequence S of an architectural feature has all been distributed for each user in the base station, and has specified receiving system 4 specific to this user for each user.What for example user n was specific is n circulation training sequence, and what user m was specific is m circulation training sequence.

Below be that example describes the communication between user and the base station with user m.

At first, the transmitter 2 of user m sends the request of access by Common Control Channel (C-CH) to the base station.The base station is after the access request that receives this user, search the TSR table, still unappropriated circulation training sequence in the retrieval base station, and a return information sent to this user m, comprise m the circulation training sequence S that distributes to this user in this return information, simultaneously, the specific receiving system 4 of the transmission information that receives this user m is specified in the base station.

The transmitter 2 of user m generates the complete frame that comprises m circulation training sequence S and user data according to m circulation training sequence S of base station assigns, and this complete frame is sent to the base station as sending signal.The receiving system 4 specific to user m of appointment in the base station, m the circulation training sequence S of user m distributed in utilization, the signal that user m is sent carries out time synchronized and Nonlinear Transformation in Frequency Offset Estimation, and by this complete frame is carried out the demodulation sign indicating number, thereby recover the user data of user m.

The operation of aforesaid user m is all carried out to the user of each access in the base station, and wherein, each user's circulation training sequence S is different with specific receiving system 4.Thereby in the uplink synchronous process of multi-user system, this communication system 1 can reduce the interference distortion that the mutual superposition owing to multi-user's training sequence causes.According to the design feature of circulation training sequence S of the present invention, can realize high-precision down-going synchronous simultaneously.

＜transmitter 2 〉

Fig. 4 has shown the structure chart of the transmitter 2 of user m, and wherein user m has received the return information that comprises the architectural feature of the circulation training sequence that is distributed from the base station.

This transmitter 2 comprises training sequence maker 20 and data symbol adder 21.Wherein, training sequence maker 20 is based on the architectural feature of the specific circulation training sequence of base station assigns, generate this specific circulation training sequence, the specific circulation training sequence that data symbol adder 21 generates according to training sequence maker 20, add this user's data symbol, form this user's complete frame.

Particularly, this training sequence maker 20 comprises encoder 201, data modulator 202, the first training symbol block of information maker 203, the first Cyclic Prefix maker 204, the second training symbol block of information maker 205 and the second Cyclic Prefix maker 206.

This transmitter 2 is behind the return information that receives from the base station, the digital coding that in training sequence maker 20, utilizes encoder 201 to carry out at random, the coding of 202 pairs of encoders of data modulator, 201 outputs is modulated, and the coded data after will modulating then is input to the first training symbol block of information maker 203 and carries out the generation of circulation training sequence.

The coded data of the first training symbol block of information maker 203 after according to modulation generates the first information piece (length of block of information is N) of first training symbol of the circulation training sequence S of user m.

The first Cyclic Prefix maker 204 is according to the first information piece of first training symbol of the first training symbol block of information maker, 203 generations, last L data of the first information piece that generates are copied, and should a last L data place before the first information piece, thereby form first training symbol as cyclic prefix CP 1.

The second training symbol block of information maker 205 is according to the architectural feature of the circulation training sequence of the user m that is distributed that comprises in the return information, the specific cycle arrangement mode of user m just, back d data in the block of information of first training symbol are displaced to before preceding (N-d) individual data of block of information, rearrange N data that obtain, thereby form the block of information of second training symbol, i.e. second block of information of circulation training sequence.

The second Cyclic Prefix maker 206 is according to the block of information of second training symbol of the second training symbol block of information maker, 205 generations, last L data of this block of information are copied as cyclic prefix CP 2, and place before second block of information, thereby form second training symbol.

Thus, training sequence maker 20 has formed circulation training sequence S of the present invention, and it comprises the Cyclic Prefix and the block of information of Cyclic Prefix and the block of information and second training symbol of first training symbol successively.

Data symbol maker 21 adds the data symbol of some according to the circulation training sequence that training sequence maker 20 generates after circulation training sequence, just add user data, thereby form a complete complete frame.The complete frame that user m utilizes wireless channel to form then sends to the base station as sending signal.

＜receiver 3 〉

Fig. 5 has shown the structural representation according to the receiver 3 of the base station of circulation training sequence S provided by the invention.

In multi-user system, when different user adopted full multiplexing transmission mode, different user may transmit complete frame separately simultaneously.In the base station, the signal that is sent by different user is superimposed.To carry out time synchronized and Nonlinear Transformation in Frequency Offset Estimation to each user according to receiver 3 of the present invention, and for the uplink synchronous of full multiplexing multiple-user system, different user synchronously can be by these receiver 3 parallel finishing.

As shown in Figure 5, receiver 3 has a plurality of receiving equipments 4, and the structure of each receiving equipment 4 is identical, and processing mode is identical, is that example describes with the receiving equipment 4 that is used for user m here.

When user m request access base station, base station assigns is for the architectural feature of the circulation training sequence of user m, second training symbol of this circulation training sequence is shifted back d data of the block of information of first training symbol and forms, generally, this d value is different from the d value of the circulation training sequence of distributing to other users.For convenience of description, the circulation training sequence of distributing to user m is called m circulation training sequence.

Among Fig. 5, the receiving equipment 4 that is used for user m comprises: synchronous and carrier wave frequency deviation device 40, demodulating equipment 41 and decoding device 42.

Be used for the signal that the receiving equipment 4 of user m sends by wireless channel according to user m, utilize synchronous and carrier wave frequency deviation device 40 realization time synchronized and Nonlinear Transformation in Frequency Offset Estimation, utilize demodulating equipment 41 and decoding device 42 to carry out the demodulation sign indicating number then respectively, thereby the signal that user m sends just can recover in the receiving equipment 4 of user m.

Wherein, at receiving equipment 4 places, the just complete frame of signal that different user sends is superimposed, and then one group of data sequence r (k) of being received of receiving equipment 4 is the stack of different user training symbol and data symbol.

Should comprise synchronously: regularly measure (Timing Metric) and Nonlinear Transformation in Frequency Offset Estimation device 51, time synchronism apparatus 58 and carrier wave frequency deviation compensation arrangement 59 with carrier wave frequency deviation device 40.

Give m the circulation training sequence of user m according to base station assigns specific to the timing tolerance of user m and Nonlinear Transformation in Frequency Offset Estimation device 51, and, from the superposition of data sequence r (k) that receives, find out the original position of the circulation training sequence S of user m according to the data sequence r that is input to time synchronism apparatus 58 (k).Searching of circulation training sequence S original position utilizes user m specific timing tolerance to receiving data sequence r (k) bit-by-bit search.When regularly local maximum result appears in tolerance, just give the architectural feature of m the circulation training sequence S of user m in base station assigns, when being complementary with the architectural feature of certain one piece of data among the receiving data sequence r (k), the starting point that the position of local maximum result will appear in receiving equipment 4 is defined as the original position of the circulation training sequence S of this user m, and then time synchronism apparatus can be realized time synchronized.

The deadline synchronously after, just in the data sequence r (k) that receives, detect m the circulation training sequence S of user m after, utilization detected m circulation training sequence S in r (k), receiving equipment 4 carries out Nonlinear Transformation in Frequency Offset Estimation for user m.

Specific to user m, just specific to timing tolerance and the Nonlinear Transformation in Frequency Offset Estimation device 51 of m circulation training sequence S, according to the receiving data sequence r (k) after the time synchronized, obtain the carrier wave frequency deviation of this user m, and be input to carrier wave frequency deviation compensation arrangement 59 with respect to receiving equipment 4.Carrier wave frequency deviation compensation arrangement 59 is according to the deadline data in synchronization sequence r (k) of time synchronism apparatus 58 outputs, and according to the carrier wave frequency deviation of regularly measuring the user m that obtains with Nonlinear Transformation in Frequency Offset Estimation device 51, it is compensated, data sequence r (k) after will compensating afterwards is sent to demodulating equipment 41 and decoding device 42, and the signal that user m is sent recovers.

＜regularly measure and the Nonlinear Transformation in Frequency Offset Estimation device

Fig. 6 has shown the structural representation of regularly measuring with Nonlinear Transformation in Frequency Offset Estimation device 51.Here at first describe the regularly process of the local maximum result of tolerance of seeking, just the signal of input is carried out the process of time synchronized.

As shown in Figure 6, regularly tolerance and Nonlinear Transformation in Frequency Offset Estimation device 51 comprise shift register 5111, first, second, third and fourth, five value modules 511,512,513,514,515; This shift register 5111, first, two, three, four value modules 511,512,513,514 have constituted regularly tolerance portion 60, this shift register 5111, first, two, five value modules 511,512,515 have constituted carrier wave frequency deviation portion 70, its operating process is: regularly tolerance portion 60 is according to the data sequence r (k) that is input to time synchronism apparatus 58, to obtaining data sequence r (L+k) after data sequence r (k) shifting processing that receives, utilize first again, two, three value modules 511,512 and 513 couples of data sequence r (L+k) carry out value to be handled, and obtains first respectively, two, three value results.Then, the 4th value module 514 is sought the regularly local maximum result of tolerance according to first, second and third value result.When local maximum result occurring, promptly detected the specific circulation training sequence S that distributes to user m, also just realized the time synchronized of data sequence.

Then, carrier wave frequency deviation portion 70 utilizes the 5th value module 515 to obtain user m in the base station carrier frequency offset estimation according to detected circulation training sequence S and first and second value result.Wherein regularly tolerance portion 60 and carrier wave frequency deviation portion 70 shared first and second value modules.

To at first specifically describe the regularly processing procedure of tolerance portion 60 below.Here establish the specific circulation training sequence S of user m and have m architectural feature.

＜timing tolerance portion 〉

Suppose data sequence r (k) that the base station receives be one group of data for r (0), r (1) ..., r (N-1) }, it at first is input to data sequence r (k) shift register 5111,5111 pairs of data sequences of shift register r (k) carries out Z ^LShifting processing (Z ^LThe delay of L position has been carried out in expression), the data r (L+k) after obtaining to be shifted.Then, data r (L+k) is input to first, second and third value module 511,512,513 respectively.Wherein, L is the length of the Cyclic Prefix of m circulation training sequence.

The first value module 511 comprises gets conjugator 5112, multiplier 5113, shift register 5114 and displacement summer 5115.

The data r (L+k) that gets 5111 inputs of 5112 pairs of shift registers of conjugator gets conjugation, and is input to multiplier 5113.Simultaneously, shift register 5114 is with m specific architectural feature of user m, and the data r (L+k) that shift register 5111 is imported carries out Z ^L+N+dShifting processing, obtain r (L+k+L+N+d) and also be input to multiplier 5113.5113 pairs of multipliers are got the data that conjugator 5112 and shift register 5114 import respectively and are carried out multiplying, according to the associative mode between the block of information of m circulation training sequence, obtain multiplication result Φ successively _{D, k}, Φ _{D, k+1}..., Φ _{D, k+N-1-d}, and be input to displacement summer 5115.N-d multiplication result of 5115 pairs of multipliers of displacement summer, 5113 inputs carries out add operation, obtains the first value result $\underset{z=k}{\overset{N+k-1-d}{\∑}}{\mathrm{\Φ}}_{d,z}.$

The second value module 512 comprises shift register 5121, gets conjugator 5122, multiplier 5123, shift register 5124 and displacement summer 5125.

The data r (L+k) of 5121 pairs of shift registers of shift register, 5111 inputs carries out Z ^N-dShifting processing, and be input to and get conjugator 5122.Get 5122 pairs of data of conjugator and get conjugation, and be input to multiplier 5123 from shift register 5121 inputs.Simultaneously, the data r (L+k) of 5124 pairs of shift registers of shift register, 5111 inputs carries out Z ^N+LShifting processing, obtain r (L+k+N+L), and be input to multiplier 5123.5123 pairs of multipliers are got the data of conjugator 5122 and shift register 5124 inputs, carry out multiplying, according to the associative mode between the block of information of m circulation training sequence, obtain multiplication result Ψ successively _{D, k}, Ψ _{D, k+1}..., Ψ _{D, k+d-1}, and be input to displacement summer 5125.5125 pairs of d multiplication results from multiplier 5123 inputs of displacement summer carry out add operation, obtain the second value result $\underset{z=k}{\overset{k+d-1}{\∑}}{\mathrm{\ψ}}_{d,z}.$

The 3rd value module 513 comprises delivery and square operation device 5131,5133, displacement summer 5132,5134, adder 5135, asks squarer 5136 and get reciprocator 5137.

The data sequence r (N+2L+k) of 5131 pairs of shift register 5124 outputs from the second value module 512 of delivery and square operation device, r (N+2L+k+1), ..., r (2N+2L+k-1) is delivery and ask square respectively, and operation result is input to displacement summer 5132 carries out add operation, thereby obtain $\underset{z=N+L+k}{\overset{2N+L+k-1}{\∑}}{\left|r(L+z)\right|}^2.$ Delivery and square operation device 5133 be according to the r (L+k) of shift register 5111 input, r (L+k+1) ..., r (N+L+k-1) delivery respectively asks square again, and N square value is input to displacement summer 5134 carries out add operation, thus acquisition $\underset{z=k}{\overset{N+k-1}{\∑}}{\left|r(L+z)\right|}^2.$ 5134 outputs of 5135 pairs of displacement summers of adder $\underset{z=k}{\overset{N+k-1}{\∑}}{\left|r(L+z)\right|}^2$ With the output of displacement summer 5132 $\underset{z=N+L+k}{\overset{2N+L+k-1}{\∑}}{\left|r(L+z)\right|}^2$ Carry out add operation, obtain addition results, and be input to and ask squarer 5136.Ask 5136 pairs of squarers squared, and a square result is input to gets reciprocator 5137 and get inverse then, thereby obtain the 3rd value result from the addition results of adder 5135 outputs.

The 4th value module 514 comprises adder 5141, delivery and squarer 5142, multiplier 5143 and asks hornwork 5144.

The first value result of 5141 pairs first value modules of adder, 511 outputs $\underset{z=k}{\overset{N+k-1-d}{\∑}}{\mathrm{\Φ}}_{d,z}$ The second value result with 512 outputs of the second value module $\underset{z=k}{\overset{k+d-1}{\∑}}{\mathrm{\ψ}}_{d,z}$ Carry out add operation, and the add operation result is outputed to delivery and squarer 5142.5142 pairs of delivery and squarers are from the add operation result elder generation deliverys of adder 5141 outputs, and be squared again, and a square result is outputed to multiplier 5143.The 3rd value result of square result of 5143 pairs of deliverys of multiplier and squarer 5142 outputs and the output of the 3rd value module carries out multiplying, and multiplication result outputed to asks hornwork 5144 greatly again.The multiplication result of asking very big again 5144 pairs of multipliers of hornwork 5143 to obtain is asked the maximum result at multiple angle, and just regularly tolerance portion 60 seeks the local maximum result by turn, when local maximum occurring as a result the time, has just realized time synchronized.

By the above, timing tolerance portion 60 specific to user m passes through shift register 5111 and first, second, third and fourth value module 511,512,513,514, searching promptly realizes time synchronized specific to the original position of m the circulation training sequence of user m.Just, this regularly tolerance portion 60 utilize specific to the timing of m the circulation training sequence of user m and measure M _d(θ):

$M_d\left(\mathrm{\θ}\right)=\frac{{|\underset{z=\mathrm{\θ}}{\overset{N+\mathrm{\θ}-1-d}{\∑}}{\mathrm{\φ}}_{d,z}+\underset{k=\mathrm{\θ}}{\overset{d+\mathrm{\θ}-1}{\∑}}{\mathrm{\ψ}}_{d,k}|}^2}{{\left[\underset{p=\mathrm{\θ}}{\overset{N+\mathrm{\θ}-1}{\∑}}({\left|r(p+L)\right|}^2+{\left|r(N+p+2L)\right|}^2)\right]}^2}---\left(1\right)$

Wherein, Φ _{D, z}=r ^*(L+z) r (N+2L+d+z), Ψ _{D, k}=r ^*(N+L-d+k) r (N+2L+k).

θ is an index in the formula (1), and the index of first data is 0.

＜carrier wave frequency deviation portion 〉

After having finished time synchronized, utilize detected m circulation training sequence S, shift register 5111 and first and second, five value modules 511,512,515 specific to the carrier wave frequency deviation portion 70 of m the circulation training sequence S of user m specific to user m, and the original position of m the circulation training sequence S that obtains according to timing tolerance portion 60 is carried out Nonlinear Transformation in Frequency Offset Estimation.Wherein carrier wave frequency deviation portion 70 and regularly tolerance portion 60 shared first and second value modules 511,512.

The 5th value module 515 comprises asks hornwork 5151,5153, multiplier 5152,5156 and adder 5155.

Ask the second value result of 5151 pairs second value modules of hornwork, 512 outputs to ask multiple angle, and be input to multiplier 5152.5152 pairs of multipliers are asked the multiple angle of hornwork 5151 output to multiply by (N-d) and (N+L+d) are obtained multiplication result $(N-d)(N+L+d)\arg \left\{\underset{z=0}{\overset{N-1-d}{\&Sum;}}{\mathrm{\&Phi;}}_{d,z}\right\}.$ Ask the first value result of 5153 pairs first value modules of hornwork, 511 outputs to ask multiple angle, and be input to multiplier 5154.5154 pairs of multipliers ask the multiple angle of hornwork 5153 outputs to multiply by d (L+d), obtain multiplication result $d(L+d)\arg \left\{\underset{k=0}{\overset{d-1}{\&Sum;}}{\mathrm{\&Psi;}}_{d,k}\right\}.$ The multiplication result that 5155 pairs of multipliers of adder 5152,5154 obtain respectively carries out add operation, and addition results is outputed to multiplier 5156.The addition results of 5156 pairs of adders of multiplier, 5155 outputs multiply by $\frac{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="H05171816420050531E000011.png,H05171816420050531E000031.png"\; state="\{\{state\}\}">N</figure-callout>}}{2\mathrm{\&pi;}[(N-d){(N+L+d)}^2+d{(L+d)}^2]},$ Thereby obtain the carrier frequency offset estimation result:

${\widehat{\&Element;}}_d=\frac{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="H05171816420050531E000011.png,H05171816420050531E000031.png"\; state="\{\{state\}\}">N</figure-callout>}}{2\mathrm{\&pi;}}\&CenterDot;\frac{(N-d)(N+L+d)\arg \left\{\underset{z=0}{\overset{N-1-d}{\&Sum;}}{\mathrm{\&phi;}}_{d,z}\right\}+d(L+d)\arg \left\{\underset{k=0}{\overset{d-1}{\&Sum;}}{\mathrm{\&psi;}}_{d,k}\right\}}{(N-d){(N+L+d)}^2+d{(L+d)}^2}---\left(2\right)$

In the formula (2) $\arg \left\{\underset{z=0}{\overset{N-1-d}{\&Sum;}}{\mathrm{\&phi;}}_{d,z}\right\},\arg \left\{\underset{k=0}{\overset{d-1}{\&Sum;}}{\mathrm{\&Psi;}}_{d,k}\right\}$ It is right to represent respectively $\underset{z=0}{\overset{N-1-d}{\&Sum;}}{\mathrm{\&Phi;}}_{d,z},\underset{k=0}{\overset{d-1}{\&Sum;}}{\mathrm{\&Psi;}}_{d,k}$ Ask multiple angle.

This carrier wave frequency deviation portion 70 is the estimators specific to d the circulation training sequence S of user m, and this estimator is condition non-partially (Conditionally Unbiased), and under the situation of high s/n ratio, its carat U.S. one sieve lower limit (CRLB) is:

$\mathrm{Var}\left\{{\widehat{\mathrm{\&epsiv;}}}_d\right\}=\frac{\mathrm{<figure-callout\; id="4"\; label="N"\; filenames="H05171816420050531E000081.png"\; state="\{\{state\}\}">N</figure-callout>}}{4{\mathrm{\&pi;}}^2({\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="H05171816420050531E000011.png,H05171816420050531E000031.png"\; state="\{\{state\}\}">N</figure-callout>}}^2+L^2-{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="H05171816420050531E000011.png,H05171816420050531E000031.png"\; state="\{\{state\}\}">d</figure-callout>}}^2+2\mathrm{NL}+\mathrm{Nd})\mathrm{SNR}}---\left(3\right)$

After finishing Nonlinear Transformation in Frequency Offset Estimation, this user m can be compensated by formula (3) at carrier wave frequency deviation compensation arrangement 59 with respect to the carrier wave frequency deviation of base station.Behind the demodulation sign indicating number, it sends signal and can be resumed.

Fig. 7 is to use the algorithm of circulation training sequence group provided by the invention and Moose algorithm application when up link, and the performance of Nonlinear Transformation in Frequency Offset Estimation is schematic diagram relatively.

Different with down-going synchronous is that in multi-user system uplink synchronous process, if a plurality of user adopts full multiplexing transmission mode, then the training sequence of different user might be superimposed in the base station.Mutual superposition between this training sequence not only reduces the effective Signal Interference and Noise Ratio of sole user (SINR), more seriously, thisly is superimposed with the inefficacy that may cause some training sequence net synchronization capability, thereby causes this user's synchronization failure.

In the simulation example shown in Figure 7, suppose to have two users to carry out uplink simultaneously.Wherein user 1 carrier wave frequency deviation is made as 0.1, and user 2 carrier wave frequency deviation is made as 0.2.User 2 signal is handled an emulation user 1 performance as user 1 interference noise in the simulation example.

When Moose algorithm application during in these two users, if two users' propagation delay time differs 288 data sampling, when promptly these two users' training sequence did not superpose in the base station, then each user can both carry out synchronous accurately.Because each user institute information transmitted can be regarded interference noise as for the another one user, thereby along with the increase of signal to noise ratio, each user's SINR increase tendency tends towards stability, and therefore under the situation of high s/n ratio, algorithm performance presents floor effect.When two users' propagation delay time differs 64 data sampling, the training sequence that is these two users is when base station portion superposes, and the Moose algorithm will lose efficacy, and consequently causes the Nonlinear Transformation in Frequency Offset Estimation error very big, and along with the increase of signal to noise ratio, evaluated error does not descend.

The algorithm application of using circulation training sequence S provided by the invention is during to uplink synchronous, and its performance is highly stable.In the simulation example, we are the circulation training sequence that user 1 distributes d=64, distribute the circulation training sequence of d=16 for user 2.As can be seen from Figure 7, estimated accuracy is apparently higher than the Moose algorithm, and the uplink synchronous performance of using circulation training sequence S of the present invention is not subjected to the influence of transmission delay, even if two users' training sequence mutual superposition, still the net synchronization capability that keeps each training sequence, and can carry out synchronous accurately.

As mentioned above, in multi-user system, when different user adopts full multiplexing transmission mode, when different user transmits separately signal simultaneously, and cause in the base station under the situation of mutual superposition of the training sequence that different user sends, according to the circulation training sequence S that arranges according to endless form of the present invention, measure M by timing specific to m the circulation training sequence of user m _d(θ) and carrier frequency offset estimator

(regularly tolerance portion 60 and carrier wave frequency deviation portion 70), can carry out time synchronized and Nonlinear Transformation in Frequency Offset Estimation to user m in the base station, thereby in the uplink synchronous process, the interference distortion that reduces multi-user's training sequence mutual superposition and cause can guarantee that each user can realize reliable and stable uplink synchronous.

＜down link 〉

For existing training sequence, conventionally form is { CP1, x (0), x (1) ..., x (N-1), CP2, x (0), x (1) ..., x (N-1) }, if relevant group the distance of data x (0) wherein, just x (0) is L with the distance of x (0), then the square distance of the relevant group of all data and be NL ²(N relevant group of data altogether).

For the circulation training sequence S of the present invention that forms according to above endless form, its form is { CP1, x (0), x (1) ..., x (N-1), CP2, x (N-d), x (N-d+1), ..., x (N-1), x (0), x (1) ..., x (N-d-1) }, wherein relevant group the distance of data x (0) is (L+d), then the square distance of the relevant group of all data and be (N-d) (L+d) ²+ d (L-d) ², can get by mathematical derivation,

NL ²＞(N-d)(L+d) ²+d(L-d) ² (4)

Yet when circulation training sequence S is applied to down-going synchronous, its attainable precision is associated with the data group square distance and is inversely proportional to, by formula (4) as can be known, since circulation training sequence S of the present invention than conventional training sequence the square distance of the relevant group of data and little, so circulation training sequence S of the present invention can realize high-precision down-going synchronous.

Fig. 8 is the schematic diagram that circulation training sequence S specific timing tolerance of the present invention changes along with the variation of SINR (Signal Interference and Noise Ratio) and synchronous error.As shown in Figure 8, for given time inclined to one side β, regularly metric is the trend of increase along with the increase of SINR.For a given SINR, the time partially more little, regularly the value of tolerance is big more.This performance makes the present invention utilize given circulation training sequence and corresponding regularly tolerance can realize that correct time is synchronous.

Fig. 9 has shown that circulation training sequence group of the present invention and Moose algorithm application are in the performance comparison figure of downlink carrier frequency offset estimating.The DFT length of two kinds of algorithms all is being made as 128, and Cyclic Prefix all is made as 16.The parameter d that algorithm of the present invention is got in the emulation shown in Figure 9=64.As seen from Figure 9, the precision of algorithm of the present invention will be higher than the Moose algorithm.In the environment of high s/n ratio, the performance of algorithm of the present invention will good 1.6dB than Moose algorithm.

Therefore, circulation training sequence S provided by the invention and communication system 1 can realize down-going synchronous accurately, simultaneously in realizing multi-user's uplink synchronous process, interference distortion between the different user that can reduce the stack between multi-user's training sequence and cause, thus can guarantee that each user can realize reliable and stable uplink synchronous.

Claims (8)

1. generation method that comprises the circulation training sequence of first training symbol and second training symbol successively, this first training symbol comprises first Cyclic Prefix and first information piece successively, and second training symbol comprises second Cyclic Prefix and second block of information successively, it is characterized in that the generation method of this circulation training sequence may further comprise the steps:

First step, generating length at random is the first information piece of N, N is a natural number;

Second step from the first information piece that generates, copies a last L data before the first information piece to, and as the Cyclic Prefix of first training symbol, wherein L is the natural number less than block of information length;

Third step, with the first information piece of first training symbol mode according to circulation, form second block of information of second training symbol identical with first information block length, wherein, before endless form is meant last d data in the first information piece is displaced to before N-d data, rearrange N data that obtain and form second block of information, the corresponding relation between this first and second block of information is the architectural feature of this circulation training sequence, and wherein d is any natural number less than block of information length; And

The 4th step copies last L data of second block of information that generates before second block of information to, as second Cyclic Prefix of second training symbol, thereby forms complete circulation training sequence.

2. communication system of using the circulation training sequence that generation method as claimed in claim 1 generated is characterized in that this communication system comprises:

User side, the architectural feature based on the specific circulation training sequence of base station assigns generates the circulation training sequence corresponding with architectural feature, adds certain data symbol, forms complete frame and sends as sending signal; And

The base station utilizes this specific circulation training sequence, and the signal that receives is carried out time synchronized and Nonlinear Transformation in Frequency Offset Estimation, and by behind the demodulation sign indicating number, recovers the transmission signal of user side.

3. communication system as claimed in claim 2 is characterized in that, this user side comprises:

Training sequence maker (20), the architectural feature based on the specific circulation training sequence of base station assigns generates this specific circulation training sequence; And

Data symbol adder (21) according to the specific circulation training sequence of described generation, adds the data symbol of this user side, forms complete frame.

4. communication system as claimed in claim 3 is characterized in that, this training sequence maker (20) comprising:

Encoder (201) is used to carry out the random data coding;

Data modulator (202) is used for the coding of encoder (201) output is modulated;

The first training symbol block of information maker (203) according to the coding after the modulation of data modulator (202) output, generates the first information piece of specific circulation training sequence;

The first Cyclic Prefix maker (204), the first information piece that generates according to the first training symbol block of information maker (203) copies last L data of the block of information that generates, and it is placed before the first information piece as first Cyclic Prefix;

The second training symbol block of information maker (205) according to the architectural feature of the specific circulation training sequence of user, before N-d data, rearranges N data that obtain and forms second block of information before back d data in the first information piece are displaced to; And

The second Cyclic Prefix maker (206), second block of information according to the generation of the second training symbol block of information maker (205), as second Cyclic Prefix, and place among second training symbol and before second block of information last L data copy of this second block of information.

5. communication system as claimed in claim 4, has receiver (3) in this base station, this receiver (3) comprises a plurality of and the corresponding receiving equipment of the circulation training sequence different structure feature (4), this each receiving equipment (4) is corresponding to a user side and corresponding to the specific circulation training sequence of this user side of base station assigns, it is characterized in that each receiving equipment (4) comprising:

Synchronously, utilize the architectural feature of this specific circulation training sequence, the data sequence of reception is carried out time synchronized and Nonlinear Transformation in Frequency Offset Estimation with carrier wave frequency deviation device (40);

Demodulating equipment (41) carries out demodulation to the output of synchronous and carrier wave frequency deviation device (40); And

Decoding device (42) is decoded to the output of demodulating equipment (41), thereby recovers the signal that the user sends.

6. communication system as claimed in claim 5 is characterized in that, this synchronously comprises regularly tolerance and Nonlinear Transformation in Frequency Offset Estimation device (51), time synchronism apparatus (58) and carrier wave frequency deviation compensation arrangement (59) with carrier wave frequency deviation device (40), wherein,

Time synchronism apparatus (58) utilizes regularly tolerance and Nonlinear Transformation in Frequency Offset Estimation device (51), to the data sequence that described base station receives, carries out time synchronized;

Regularly measure and Nonlinear Transformation in Frequency Offset Estimation device (51), give the architectural feature of user's specific circulation training sequence according to described base station assigns, described data sequence bit-by-bit search is arrived specific to the original position of this user's circulation training sequence, carry out Nonlinear Transformation in Frequency Offset Estimation synchronously in the deadline; And

Carrier wave frequency deviation compensation arrangement (59), the Nonlinear Transformation in Frequency Offset Estimation result who utilizes regularly tolerance and Nonlinear Transformation in Frequency Offset Estimation device (51) to obtain carries out the carrier wave frequency deviation compensation to this user.

7. communication system as claimed in claim 6 is characterized in that, this regularly measures the architectural feature specific timing tolerance M that utilizes described circulation training sequence with Nonlinear Transformation in Frequency Offset Estimation device (51) _d(θ), to data sequence r (z) bit-by-bit search that receives, with M _d(θ) position that local maximum occurs is defined as the original position of circulation training sequence described in the data sequence r (z); And this timing tolerance and Nonlinear Transformation in Frequency Offset Estimation device (51) utilize the architectural feature particular carrier wave frequency offset estimating of described circulation training sequence

With the original position of circulation training sequence described in the data sequence r (z), this user is carried out Nonlinear Transformation in Frequency Offset Estimation; Wherein

$M_d\left(\mathrm{\&theta;}\right)=\frac{{|\underset{z=\mathrm{\&theta;}}{\overset{N+\mathrm{\&theta;}-1-d}{\mathrm{\&Sigma;}}}{\mathrm{\&phi;}}_{d,z}+\underset{k=\mathrm{\&theta;}}{\overset{d+\mathrm{\&theta;}-1}{\mathrm{\&Sigma;}}}{\mathrm{\&psi;}}_{d,k}|}^2}{{\left[\underset{p=\mathrm{\&theta;}}{\overset{N+\mathrm{\&theta;}-1}{\mathrm{\&Sigma;}}}({\left|r(p+L)\right|}^2+{\left|r(N+p+2L)\right|}^2)\right]}^2}$

Φ _{D, z}=r ^*(L+z) r (N+2L+d+z), Ψ _{D, k}=r ^*(N+L-d+k) r (N+2L+k), θ is an index, and the index of first data of data sequence r (z) is 0, d is the natural number corresponding to the architectural feature of described circulation training sequence, N is the length of first or second block of information of described circulation training sequence, r* (L+z) gets conjugation to r (L+z)

${\widehat{\mathrm{\&epsiv;}}}_d=\frac{N}{2\mathrm{\&pi;}}\&CenterDot;\frac{(N-d)(N+L+d)\arg \left\{\underset{z=0}{\overset{N-1-d}{\mathrm{\&Sigma;}}}{\mathrm{\&Phi;}}_{d,z}\right\}+d(L+d)\arg \left\{\underset{k=0}{\overset{d-1}{\mathrm{\&Sigma;}}}{\mathrm{\&Psi;}}_{d,k}\right\}}{(N-d){(N+L+d)}^2+d{(L+d)}^2},$

It is right to represent respectively Ask multiple angle.

8. communication means that utilizes the circulation training sequence that generation method as claimed in claim 1 generated is characterized in that this communication means comprises step:

First step, the user sends the request of access by Common Control Channel to the base station;

Second step: the circulation training sequence resource table is searched in the base station after the access request that receives this user, and there are a plurality of circulation training sequences with different structure feature in still unappropriated training sequence in the retrieval base station in this circulation training sequence resource table;

Third step, the base station is from the still unappropriated circulation training sequence that retrieves, select one of them, and send an answer message to this user, the distribution condition of notice circulation training sequence, refresh the distribution operating position of circulation training sequence in the circulation training sequence resource table of base station simultaneously, wherein, include the specific architectural feature of this circulation training sequence in this return information;

The 4th step, the user generates complete frame and sends it to the base station according to the specific architectural feature of the circulation training sequence that is comprised in the return information that receives, and wherein, this complete frame comprises data symbol and specific to user's circulation training sequence; And

The 5th step, receiving system carries out time synchronized and Nonlinear Transformation in Frequency Offset Estimation to the signal that this user sends in the base station, and behind the demodulation sign indicating number, recovers user's transmission signal.

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